pgnppl

My son borrowed my old truck and it cut off on him driving down the highway.It was running fine before it cut off. He tried putting gas in the carb and turning it over before I got there. No response. I pulled it home and checked for spark. It has spark all the way to the plugs. The distributor cap and everything under it was replaced about a year ago.The injectors are firing and the truck is turning over fine. No rattles or odd noises. I replaced the fuel pump and filter about six months ago. It doesn`t sound as if it has jumped time. It is a 1993 Cheyenne with a six cylinder. The truck was rewired by someone before I got it. So that may complicate things. Does anyone have any ideas what it could be. It has spark and fuel.Thanks

meternerd

Hmmm...fuel in the carb, but the injectors are firing. Makes no sense. Anyway...spark OK (at the right time "timing") , fuel OK, compression OK, engine should fire. You need to verify all of these, starting with ignition. If you are getting spark, then fuel is the next step. How do you know the injectors are working? Could be a fuel pump problem. You need to narrow it down. Use a timing light to verify ignition and a small squirt of fuel into the throttle body should at least get it to fire.

pgnppl

I tried adding fuel. The truck would not hit. The injectors are working because I can see them spraying. The fuel pressure could be off but I doubt it. Everything is new and the truck should have tried to fire anyway. I was about to replace the timing gears and chain when he borrowed the truck. It doesn`t sound like anything is wrong with the timing when it is turned over but I am going to assume the chain has jumped and start there. I was about to do it anyway.

kevinkpk

Does it have injectors or a carb? What color is the spark, assumming it electronic spark

meternerd

Have you done a compression check? Have you verified ignition timing with a light? A jumped chain should effect both timing and compression. You could pull the valve covers and to a "static" timing check (rotor pointing to "1 when on compression stroke (both valves closed)). If that seems to be OK, then your chain is likely where it should be. Have you verified firing order for the plug wires? Just some thoughts. I'm not trying to "talk down" to you, but all kinds of people read these threads and some may have more or less experience. No offense. Have you watched the spark across the plug with it grounded to the engine while removed? If you're getting nothing as far as trying to start, something is major wrong. Any engine with fuel/air ratio OK, ignition at the right moment and compression OK should at least pop. You could also disconnect the injector wires and then do the "squirt" test. It could be flooding out. Any raw gas smell from the exhaust? Keep us informed of your progress.

kevinkpk

Need to determine first is it carburetion, or fuel injection? Is what he posting as injectors, rocker arms ? If it's a stock 93, it will be fuel injection with electronic ignition, with that is the spark arc white, yellow?